JP4686952B2 - Driving force transmission device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a driving force transmission device that can stabilize the attractive force of an armature by energization of an electromagnet.
[0002]
[Prior art]
The present applicant has proposed a driving force transmission device shown in FIGS. 6 and 7 that is disposed between a propeller shaft and a drive pinion shaft of a vehicle and transmits torque between the shafts.
[0003]
6 and 7, the left side is the front side and the right side is the rear side.
FIG. 6 is a schematic view of the vehicle 12, in which the driving force transmission device 11 is supported in the accommodated state by the differential carrier 22, and the propeller shaft 18 and the drive pinion shaft 19 are connected to the driving force transmission device 11. .
[0004]
As shown in FIG. 7, the driving force transmission device 11 includes an outer case 30a as an outer rotating member, an inner shaft 30b as an inner rotating member, a main clutch mechanism 30c, a pilot clutch mechanism 30d, and a cam mechanism 30e.
[0005]
The outer case 30a includes a bottomed cylindrical front housing 31a and a rear housing 31b that is screwed to the rear end opening of the front housing 31a and covers the opening. An input shaft 50 projects from the front end portion of the front housing 31a, and the propeller shaft 18 is connected to the input shaft 50 (see FIG. 6).
[0006]
The front housing 31a and the rear housing 31b in which the input shaft 50 is integrally formed are made of magnetic material iron. A stainless steel cylinder 51 made of a nonmagnetic material is embedded in the radial middle portion of the rear housing 31b, and the cylinder 51 forms an annular nonmagnetic portion.
[0007]
The front housing 31a has a front end outer periphery that is rotatably supported by a differential carrier 22 (see FIG. 6) via a bearing (not shown). The rear housing 31b is supported such that the outer periphery of the intermediate portion in the direction of the axis O is rotatable relative to a yoke 36 supported by the differential carrier 22 via a bearing 40.
[0008]
The bearing 40 corresponds to a radial bearing.
The inner shaft 30b penetrates the central portion of the rear housing 31b in a liquid-tight manner, is inserted into the front housing 31a, and the movement of the driving force transmission device 11 in the direction of the axis O is restricted and the It is supported so as to be rotatable relative to the housing 31b. A drive pinion shaft 19 is inserted into the inner shaft 30b (see FIG. 6).
[0009]
The main clutch mechanism 30c is a wet multi-plate friction clutch mechanism, and includes a large number of inner clutch plates 32a and outer clutch plates 32b, and is disposed on the front side in the front housing 31a.
[0010]
Each inner clutch plate 32a constituting the friction clutch mechanism is assembled by being spline fitted to the outer periphery of the inner shaft 30b so as to be movable in the direction of the axis O. On the other hand, each outer clutch plate 32b is spline-fitted to the inner periphery of the front housing 31a and assembled so as to be movable in the direction of the axis O. The inner clutch plates 32a and the outer clutch plates 32b are alternately positioned so as to come into contact with each other and frictionally engage with each other, and are separated from each other to be in an unengaged free state.
[0011]
The pilot clutch mechanism 30d includes an electromagnet 33, a friction clutch 34, and an armature 35.
The yoke 36 is supported in a state where it is inserted into the differential carrier 22 by so-called mark soldering fitting. An annular electromagnet 33 is fitted on the yoke 36, and the electromagnet 33 is fitted in an annular recess 53 of the rear housing 31b.
[0012]
A first magnetic flux passage ridge 61 is formed at a portion of the rear housing 31b facing the outer peripheral surface of the yoke 36, and a second magnetic flux passage ridge 62 is formed at a portion of the yoke 36 facing the first magnetic flux passage ridge 61. Is formed. A third magnetic flux passage ridge 63 is formed at a portion of the rear housing 31b facing the inner peripheral surface of the yoke 36, and a fourth magnetic flux passage is formed at a portion of the yoke 36 facing the third magnetic flux passage ridge 63. A protrusion 64 is formed. The tip surfaces of the first to fourth magnetic flux passage ridges 61 to 64 are formed to be parallel to the axis O. A predetermined gap is formed between the first magnetic flux passage ridge 61 and the second magnetic flux passage ridge 62 and between the third magnetic flux passage ridge 63 and the fourth magnetic flux passage ridge 64.
[0013]
The friction clutch 34 is configured as a multi-plate friction clutch including a plurality of inner clutch plates 34a and an outer clutch plate 34b. Each inner clutch plate 34a is spline-fitted to the outer periphery of a first cam member 37 constituting a cam mechanism 30e described later, and is assembled so as to be movable in the direction of the axis O. On the other hand, each outer clutch plate 34b is spline-fitted to the inner periphery of the front housing 31a and assembled so as to be movable in the direction of the axis O.
[0014]
The inner clutch plates 34a and the outer clutch plates 34b are alternately positioned so as to come into contact with each other and frictionally engage with each other, and are separated from each other to be in a non-engaged free state.
[0015]
The armature 35 has an annular shape and is assembled so as to be movable in the direction of the axis O by being spline-fitted to the inner periphery of the front housing 31a. The armature 35 is positioned in front of the friction clutch 34 and faces the friction clutch 34.
[0016]
By energizing the electromagnetic coil of the electromagnet 33, the yoke 36, the second magnetic flux passage ridge 62, the first magnetic flux passage ridge 61, the rear housing 31b, the friction clutch 34, the armature 35, the friction clutch 34, the rear housing 31b, the third A magnetic path Z that circulates between the magnetic flux passage ridge 63, the fourth magnetic flux passage ridge 64, and the yoke 36 is formed.
[0017]
The cam mechanism 30 e includes a first cam member 37, a second cam member 38, and a cam follower 39.
In the first cam member 37 and the second cam member 38, a plurality of cam grooves (not shown) facing each other are formed in the circumferential direction at predetermined intervals in the circumferential direction. The first cam member 37 is rotatably inserted into the outer periphery of the inner shaft 30b and is rotatably supported by the rear housing 31b. Each inner clutch plate 34 a is splined to the outer periphery of the first cam member 37.
[0018]
The second cam member 38 is spline-fitted to the outer periphery of the inner shaft 30b, and is assembled to the inner shaft 30b so as to be integrally rotatable. The second cam member 38 is positioned to face the inner clutch plate 32a of the main clutch mechanism 30c. A ball-shaped cam follower 39 is interposed in the cam grooves of the second cam member 38 and the first cam member 37 facing each other.
[0019]
As a result, in the front housing 31a, the armature 35 is located on the front side of the friction clutch 34, and the electromagnet 33 is located on the rear side of the friction clutch 34 with the rear housing 31b interposed therebetween. The rear housing 31b serves as a magnetic path forming member. Function.
[0020]
The rear housing 31b is screwed to the front housing 31a at the peripheral edge portion of the front side wall thereof in a state of being inserted in a liquid-tight and rotatable manner on the outer periphery of the inner shaft 30b. The rear housing 31b is supported in a liquid-tight and rotatable manner on the differential carrier 22 via an oil seal (not shown) on the outer periphery of the rear end portion of the rear cylinder portion.
[0021]
The driving force transmission device 11 does not form the magnetic path Z when the electromagnetic coil of the electromagnet 33 is not energized, and the friction clutch 34 is in a non-engaged state. Therefore, the pilot clutch mechanism 30d is in an inoperative state, and the first cam member 37 constituting the cam mechanism 30e can rotate integrally with the second cam member 38 via the cam follower 39, and the main clutch mechanism 30c. Is inactive.
[0022]
On the other hand, when the electromagnetic coil of the electromagnet 33 is energized, a magnetic path Z is formed in the pilot clutch mechanism 30d, the electromagnet 33 attracts the armature 35, and the armature 35 presses and frictionally engages the friction clutch 34. Then, the first cam member 37 of the cam mechanism 30e rotates in accordance with the rotation of the outer case 30a from the state in which the first cam member 37 rotates integrally with the second cam member 38. Then, relative rotation occurs between the first cam member 37 and the second cam member 38, and the cam follower 39 moves in the cam grooves of both the cam members 37 and 38. By the movement of the cam follower 39, the cam follower 39 presses both the cam members 37 and 38 away from each other in the cam mechanism 30e.
[0023]
As a result, the second cam member 38 is pressed toward the main clutch mechanism 30c, causing the main clutch mechanism 30c to frictionally engage according to the friction engagement force of the friction clutch 34, and the torque between the outer case 30a and the inner shaft 30b. Make a transmission.
[0024]
Further, when the voltage current to the electromagnetic coil of the electromagnet 33 is increased to a predetermined value, the attractive force of the electromagnet 33 to the armature 35 increases. Then, the armature 35 is strongly attracted toward the electromagnet 33 and increases the friction engagement force of the friction clutch 34. Then, the first cam member 37 is less likely to slip with respect to the rotation of the outer case 30a, and as a result, the relative rotation between the cam members 37 and 38 is increased. As a result, the cam follower 39 increases the pressing force with respect to the second cam member 38 to bring the main clutch mechanism 30c into the coupled state.
[0025]
[Problems to be solved by the invention]
By the way, as shown in FIG. 8, the bearing 40 includes an inner ring 40a, an outer ring 40b, and a bearing ball 40c disposed between both the rings 40a and 40b. A ball groove for receiving the bearing ball 40c is formed in the inner ring 40a and the outer ring 40b, and the curvature radius of the ball groove is formed slightly larger than the curvature radius of the bearing ball 40c. In this way, a slight gap is formed between the ball groove and the bearing ball 40c by making the curvature radius of the ball groove slightly larger than the curvature radius of the bearing ball 40c. By providing this gap, seizure between the ball groove and the bearing ball 40c is prevented.
[0026]
Hereinafter, this slight gap is referred to as “residual angular gap”.
However, since the radius of curvature of the ball groove is larger than the radius of curvature of the bearing ball 40c, the outer ring 40b moves in parallel in the front-rear direction and the direction perpendicular to the axis O with respect to the inner ring 40a (rear housing 31b) in FIG. Sometimes. Further, in FIG. 7, the robot is rattling by rotating in a clockwise direction or a counterclockwise direction with a virtual line centered on the center point C and perpendicular to the paper surface as a rotation axis. Hereinafter, the clockwise direction or the counterclockwise direction around the center point C of the bearing 40 is referred to as a “circumferential direction”.
[0027]
The center point C here is a point located on the axis O and in the center of the bearing 40 in the direction of the axis O. The “clockwise direction or counterclockwise direction about the center point C” corresponds to “the rotational direction about the virtual line orthogonal to the axis of the radial bearing”.
[0028]
The backlash of the outer ring 40b in the front-rear direction and the direction orthogonal to the axis O is not so large, but the backlash of the outer ring 40b in the circumferential direction is large.
[0029]
As shown in FIG. 8, when the outer ring 40b rattles in the circumferential direction, the tip surface of the second magnetic flux passage ridge 62 and the tip surface of the fourth magnetic flux passage ridge 64 are parallel to the axis O. The gap between the first magnetic flux passage ridge 61 and the second magnetic flux passage ridge 62 and the width of the gap between the third magnetic flux passage ridge 63 and the fourth magnetic flux passage ridge 64 are greatly changed. . Since this gap is a magnetic resistance when the magnetic path Z is formed, the density of the magnetic flux passing through the magnetic path Z becomes unstable if the width changes greatly. As a result, even when the current applied to the electromagnet 33 is always constant, the magnetic flux density passing through the magnetic path Z varies greatly from time to time, and the force with which the electromagnet 33 attracts the armature 35 is unstable.
[0030]
Further, when the first magnetic flux passage ridge 61, the second magnetic flux passage ridge 62, the third magnetic flux passage ridge 63, and the fourth magnetic flux passage ridge 64 collide due to the rattling in the circumferential direction, There will be chatter. Furthermore, when the yoke 36 on the fixed side comes into contact with the rear housing 31b on the rotating side, wear, chipping, etc. may occur, and the magnetic flux density at the beginning of assembly may not be maintained.
[0031]
Furthermore, the rear housing 31b and the yoke 36 may be fixed to each other, which may cause a rotation failure of the propeller shaft 18, breakage of the rear housing 31b and the yoke 36, and the like. Therefore, in order to prevent the collision, it is necessary to design the gaps of the first magnetic flux passage ridge 61 and the second magnetic flux passage ridge 62 and the third magnetic flux passage ridge 63 and the fourth magnetic flux passage ridge 64 as wide as possible. In some cases, the force that the electromagnet 33 attracts the armature 35 becomes weaker as the gap becomes wider.
[0032]
The present invention has been made in view of the above-described circumstances, and an object thereof is to provide a driving force transmission device capable of stabilizing the attractive force of an armature by energization of an electromagnet.
[0033]
[Means for Solving the Problems]
  In order to solve the above-mentioned problems, the invention according to claim 1 includes an inner rotating member and an outer rotating member positioned so as to be relatively rotatable, and a friction clutch for transmitting torque between the inner rotating member and the outer rotating member. An armature disposed opposite to the friction clutch, an electromagnet disposed opposite to the armature across the friction clutch, a yoke supporting the electromagnet, and the yoke with respect to the outer rotating member via a gap. To support relative rotationbearingA magnetic path that circulates through the yoke, outer rotating member, friction clutch, armature, friction clutch, outer rotating member, and yoke by energizing the electromagnet, and the electromagnet attracts the armature to form the friction. In the driving force transmission device configured to frictionally engage the clutch and connect the both rotating members to transmit torque by the frictional engagement force of the friction clutch, the outer rotating member in the magnetic path of the yoke The first facing surface that is the surface facing thebearingFormed on a curved surface along a virtual sphere centered on the center point ofAnd a second facing surface that is a surface facing the yoke in the magnetic path of the outer rotating member is formed as a curved surface along a virtual spherical surface centered on the center point of the bearing.It is a summary.
[0034]
  In the driving force transmission device according to claim 1,bearingHas an inner ring and an outer ring. Looking at the inner ring as a reference, the outer ring and the yoke arebearingIt rotates slightly in the rotation direction around a virtual line perpendicular to the axis of the axis. However, the first opposing surface of the yoke through which the magnetic path passes isbearingTherefore, the width of the air gap in the first facing surface portion hardly changes. For this reason, the magnetic flux density passing through the magnetic path is stabilized.
  Further, the second facing surface of the outer rotating member through which the magnetic path passes is also formed as a curved surface along a virtual spherical surface centered on the center point of the bearing. For this reason, even if the outer ring and the yoke are slightly rotated in the rotation direction around a virtual line orthogonal to the bearing axis, the width of the gap formed by the first facing surface and the second facing surface is hardly changed. . Therefore, the gap management becomes easy.
[0035]
  The invention according to claim 2 is the driving force transmission device according to claim 1,The gist of the invention is that the bearing includes an inner ring, an outer ring, and a bearing ball disposed between the inner ring and the outer ring.
  The invention according to claim 3 is the driving force transmission device according to claim 1 or 2,The gist is that the first facing surface is disposed in a protruding portion protruding toward the outer rotating member.
[0036]
  Claim3In the driving force transmission device according to claim 1,Or claim 2In addition to the operation of the driving force transmission device described in (1), by forming a protrusion on the yoke, there is an effect that the magnetic path can be easily guided to the protrusion.
[0039]
  The invention according to claim 4 is the claim1-claim3Any one ofIn the driving force transmission device according to the item, the second opposing surface is arranged in a protruding portion protruding toward the yoke.
  In the driving force transmission device according to claim 4,1-claim3Any one ofIn addition to the operation of the driving force transmission device described in (1), by forming the protrusion on the outer rotating member, there is an effect that not only the magnetic path can be easily guided to the protrusion but also the gap management becomes easy.
[0040]
DETAILED DESCRIPTION OF THE INVENTION
(First embodiment)
A first embodiment embodying the present invention will be described below with reference to FIG. In the present embodiment, the same parts as those in the prior art are denoted by the same reference numerals, detailed description thereof is omitted, and only different parts are described.
[0041]
In the driving force transmission device 81 of the present embodiment, the tip surface 61a of the first magnetic flux passage ridge 61 is formed as a curved surface along a virtual spherical surface with the center point C as the center. In the present embodiment, the tip surface 62a of the second magnetic flux passage ridge 62 is also formed as a curved surface along a virtual spherical surface with the center point C as the center.
[0042]
Further, the second magnetic flux passage ridge 62 is formed so that the tip surface 62a can always face the entire surface of the tip surface 61a even when the yoke 36 rotates in the circumferential direction.
In the present embodiment, the friction clutch 34 corresponds to the friction clutch in the claims, the first magnetic flux passage protrusion 61 corresponds to the protrusion, and the tip surface 61a corresponds to the second facing surface. Moreover, the 2nd magnetic flux passage protrusion 62 is corresponded to a protrusion part, and the front end surface 62a is corresponded to a 1st opposing surface.
[0043]
Next, the operation of the driving force transmission device 81 of the first embodiment will be described.
During the driving of the driving force transmission device 81, the yoke 36 rotates around the center point C due to vibration generated by the relative rotation of the outer case 30a (rear housing 31b) and the yoke 36 and the residual angular gap of the bearing 40. Rotate slightly in the direction.
[0044]
However, since the tip surface 61a and the tip surface 62a are formed along a virtual spherical surface with the center point C as the center, even if the yoke 36 is slightly rotated in the circumferential direction around the center point C, The width of the gap formed by the two end surfaces 61a and 62a hardly changes. For this reason, the force that the electromagnet 33 attracts the armature 35 and the magnetic flux density that passes through the magnetic path Z are stable as compared with the driving force transmission device 11 of the prior art, and the gap formed by the both end surfaces 61a and 62a is minimized. Can be designed as narrow as possible.
[0045]
Hereinafter, in the present embodiment, the gap formed by the both end surfaces 61a and 62a may be simply referred to as a gap.
Therefore, according to the driving force transmission device 81 of the first embodiment, the following effects can be obtained.
[0046]
(1) In this embodiment, the front end surface 61a of the first magnetic flux passage ridge 61 and the front end surface 62a of the second magnetic flux passage ridge 62 are respectively formed on curved surfaces along a virtual spherical surface with the center point C as the center. did. Therefore, even if the yoke 36 is slightly rotated in the circumferential direction around the center point C due to the residual angular gap of the bearing 40, the width of the gap formed by the both end surfaces 61a and 62a hardly changes. Therefore, as compared with the conventional driving force transmission device 11, the driving force transmission device 81 of the present embodiment can stabilize the attraction force of the armature 35 by energization of the electromagnet 33. As a result, the driving force transmission device 81 can be formed with a narrower gap than the driving force transmission device 11. Moreover, both the end surfaces 61a and 62a do not collide with each other, and abnormal noise, chatter, wear, chipping, and the like due to the collision can be prevented. In addition, since the tip surfaces 61a and 62a are not worn or chipped by the collision, the magnetic flux density passing between the tip surfaces 61a and 62a can maintain the initial state of assembly.
[0047]
(2) Further, in the driving force transmission device 81 according to the present embodiment, the force with which the electromagnet 33 attracts the armature 35 is stabilized as compared with the driving force transmission device 11, and the width of the gap is larger than that of the driving force transmission device 11. By narrowing, even if it is the same energization amount as the driving force transmission apparatus 11, an attraction force increases. Therefore, the number of plates 32a, 32b or plates 34a, 34b can be reduced or the size can be reduced. As a result, the driving force transmission device 81 itself can be reduced in size. Hereinafter, the reason why the driving force transmission device 81 itself can be reduced in size will be described.
[0048]
When the force with which the electromagnet 33 attracts the armature 35 is not stable, the driving force transmission device 81 must be configured assuming that the attraction force is weakest. If the tip surfaces 61a and 62a are parallel to the axis O, it is necessary to provide a wide gap width in consideration of the rattling of the yoke 36 in the circumferential direction. Is weakened, and the force for frictionally engaging the plates 34a and 34b is also weakened. For this reason, the force with which the second cam member 38 frictionally engages both the plates 32a and 32b is weakened, and torque transmission between the outer case 30a and the inner shaft 30b is not desired.
[0049]
Therefore, in order to compensate for the weakness of the force by which the armature 35 frictionally engages both the plates 32a and 32b, it is conceivable to increase the contact area of both the plates 32a and 32b. As a specific method of increasing the contact area, it is conceivable to increase the number of both plates 32a and 32b or to increase the size. As a result, torque transmission between the outer case 30a and the inner shaft 30b can be sufficiently performed, but the entire driving force transmission device 81 is increased in size.
[0050]
Further, instead of increasing the number of both plates 32a and 32b or increasing the size, it is possible to increase the number of both plates 34a and 34b of the pilot clutch mechanism 30d or increase the size. Even if it does in this way, although torque transmission between the outer case 30a and the inner shaft 30b can fully be performed, the driving force transmission device 81 whole will also enlarge.
[0051]
Therefore, if the force with which the electromagnet 33 attracts the armature 35 is stable and the width of the gap can be minimized, the number of both plates 32a, 32b or both plates 34a, 34b can be increased or the size can be increased accordingly. There is no need to do.
[0052]
Therefore, the driving force transmission device 81 of this embodiment can reduce the number of both plates 32a and 32b or both plates 34a and 34b or reduce the size as compared with the driving force transmission device 11 of the prior art. The transmission device 81 itself can be reduced in size.
[0053]
(3) In the present embodiment, the tip surface 62 a that forms a curved surface (a curved surface along a virtual spherical surface with the center point C as the center) is formed on the second magnetic flux passage ridge 62. Therefore, compared with the case where the same curved surface as the tip end surface 62a is formed in a recessed portion or a flat portion, in the present embodiment, the protruding portion is formed on the protruding second magnetic flux passage ridge 62, so that it is easy to form.
[0054]
(4) In the present embodiment, the second magnetic flux passage protrusion 62 is formed on the yoke 36. Therefore, in the vicinity of the second magnetic flux passage ridge 62, the second magnetic flux passage ridge 62 is closest to the rear housing 31b (first magnetic flux passage ridge 61). The magnetic path can be easily guided and the width of the air gap can be easily managed.
[0055]
(5) In the present embodiment, the tip surface 61 a that forms a curved surface (a curved surface along a virtual spherical surface with the center point C as the center) is formed on the first magnetic flux passage ridge 61. Therefore, compared to the case where the same curved surface as the tip surface 61a is formed in a recessed portion or a flat portion, in the present embodiment, the protruding first magnetic flux passage protrusion 61 is formed, so that it is easy to form.
[0056]
(6) In this embodiment, the 1st magnetic flux passage protrusion 61 was formed in the rear housing 31b. Therefore, in the vicinity of the first magnetic flux passage ridge 61, since the first magnetic flux passage ridge 61 is closest to the yoke 36 (second magnetic flux passage ridge 62), the width of the air gap can be easily managed. In addition, the magnetic path Z can be easily guided to the first magnetic flux passage ridge 61.
[0057]
(7) In the present embodiment, the second magnetic flux passage ridge 62 is formed so that the tip surface 62a can always face the entire surface of the tip surface 61a even when the yoke 36 rotates in the circumferential direction. Therefore, the attractive force of the armature 35 due to the energization of the electromagnet 33 can be further stabilized.
[0058]
(Second Embodiment)
Next, a second embodiment of the present invention will be described with reference to FIG. In the present embodiment, the same parts as those in the first embodiment are denoted by the same reference numerals, detailed description thereof is omitted, and only different parts are described.
[0059]
In the driving force transmission device 91 of the present embodiment, the tip surface of the first magnetic flux passage ridge 61 is different from that of the first embodiment. The tip surface 70 of the first magnetic flux passage ridge 61 of the present embodiment is formed along the surface of a virtual cone having the axis O as the axis. The tip surface 70 is a slope that approaches the axis O as it goes forward.
[0060]
Furthermore, even if the yoke 36 rotates in the circumferential direction, the second magnetic flux passage ridge 62 is formed so that the tip surface 62a can always face the entire surface of the tip surface 70.
Next, the operation of the driving force transmission device 91 of the second embodiment will be described.
[0061]
The front end surface 62a is formed along a virtual spherical surface centered on the center point C, and the front end surface 70 is formed along the surface of a virtual cone centering on the axis O. For this reason, even if the yoke 36 is slightly rotated in the circumferential direction around the center point C, the width of the gap formed by the two end faces 70 and 62a hardly changes. Therefore, the width of the gap can be designed to be minimized. It becomes.
[0062]
Therefore, according to the driving force transmission device 91 of the second embodiment, the same effects as the effects (2) to (4), (6), and (7) of the first embodiment are obtained, and as follows. Effects can be obtained.
[0063]
(1) In this embodiment, the front end surface 70 of the first magnetic flux passage ridge 61 is formed as a curved surface along the surface of a virtual cone having the axis O as the axis. Further, the tip surface 62a of the second magnetic flux passage ridge 62 is formed into a curved surface along a virtual spherical surface with the center point C as the center. Therefore, even if the yoke 36 is slightly rotated in the circumferential direction around the center point C due to the residual angular gap of the bearing 40, the width of the gap formed by the two end surfaces 70 and 62a hardly changes. Therefore, as compared with the conventional driving force transmission device 11, the driving force transmission device 91 according to the present embodiment can stabilize the attractive force of the armature 35 by energization of the electromagnet 33. As a result, the driving force transmission device 91 can make the width of the gap formed by the both end surfaces 70 and 62 a narrower than that of the driving force transmission device 11. Moreover, both the end surfaces 62a and 70 do not collide with each other, and abnormal noise, chattering, wear, chipping, and the like due to the collision can be prevented. In addition, since both the tip surfaces 62a and 70 are not worn and chipped by the collision, the magnetic flux density passing between the two tip surfaces 62a and 70 can maintain the initial state of assembly.
[0064]
(Third embodiment)
Next, a third embodiment of the present invention will be described with reference to FIG. In the present embodiment, the same parts as those in the prior art are denoted by the same reference numerals, detailed description thereof is omitted, and only different parts are described.
[0065]
In the driving force transmission device 101 of the present embodiment, the first magnetic flux passage ridge 61 is omitted, and a recess 71 is formed on the rear end side from the portion where the first magnetic flux passage ridge 61 is formed. Yes. The bottom surface (surface) 71a of the recess 71 is formed in a curved surface along a virtual spherical surface with the center point C as the center.
[0066]
Moreover, the 2nd magnetic flux passage protrusion 62 of this embodiment protrudes long compared with the 2nd magnetic flux passage protrusion 62 of a prior art. And the front end surface 62a of the 2nd magnetic flux passage protrusion 62 is formed in the curved surface which follows the virtual spherical surface centering on the center point C. As shown in FIG.
[0067]
In the present embodiment, the bottom surface 71a corresponds to a second facing surface. Moreover, the 2nd magnetic flux passage protrusion 62 is corresponded to a protrusion part, and the front end surface 62a is corresponded to a 1st opposing surface.
Therefore, according to the driving force transmission device 101 of the third embodiment, the same operation as that of the driving force transmission device 81 of the first embodiment is achieved. Moreover, according to the said 3rd Embodiment, while obtaining the effect similar to the effect of (2)-(4) of 1st Embodiment, the following effects can be acquired.
[0068]
(1) In the present embodiment, the bottom surface 71a of the recess 71 and the tip surface 62a of the second magnetic flux passage ridge 62 are formed into curved surfaces along a virtual spherical surface with the center point C as the center. Therefore, even if the yoke 36 is slightly rotated in the circumferential direction around the center point C due to the residual angular gap of the bearing 40, the width of the gap formed by the both surfaces 71a and 62a hardly changes. Therefore, as compared with the conventional driving force transmission device 11, the driving force transmission device 101 of the present embodiment can stabilize the attractive force of the armature 35 due to the energization of the electromagnet 33. As a result, in the driving force transmission device 101, the width of the gap formed by the both surfaces 71a and 62a can be narrower than that of the driving force transmission device 11. Moreover, the front end surface 62a and the bottom surface 71a do not collide with each other, and abnormal noise, chattering, wear, chipping, and the like due to the collision can be prevented. In addition, since there is no wear or chipping due to the collision between the tip surface 62a and the bottom surface 71a, the magnetic flux density passing between the tip surface 62a and the bottom surface 71a can maintain the initial state of assembly.
[0069]
(2) In the present embodiment, the bottom surface 71a having a curved surface (a curved surface along a virtual spherical surface with the center point C as the center) is formed in the recess 71. That is, the bottom surface 71a is formed on the inner surface of the rear end of the rear housing 31b. Therefore, it is easier to form the same curved surface as the bottom surface 71a than in the case where the curved surface is formed in a flat portion that is not an end portion.
[0070]
(Fourth embodiment)
Next, a fourth embodiment embodying the present invention will be described with reference to FIG. In the present embodiment, the same parts as those in the third embodiment are denoted by the same reference numerals, detailed description thereof is omitted, and only different parts are described.
[0071]
In the driving force transmission device 111 of the present embodiment, the bottom surface of the recess 71 is different from that of the third embodiment. The bottom surface 72 of the recess 71 of the present embodiment is formed along the surface of a virtual cone with the axis O as the axis. The bottom surface 72 has a slope that approaches the axis O as it goes forward.
[0072]
Next, the operation of the driving force transmission device 111 according to the fourth embodiment will be described.
The distal end surface 62a is formed along a virtual spherical surface centered on the center point C, and the bottom surface 72 is formed along the surface of a virtual cone centering on the axis O. Therefore, even if the yoke 36 is slightly rotated in the circumferential direction around the center point C, the width of the gap formed by the bottom surface 72 and the tip surface 62a hardly changes. It becomes.
[0073]
Therefore, according to the driving force transmission device 111 of the fourth embodiment, the same effects as the effects (2) to (4) of the first embodiment can be obtained, and the following effects can be obtained.
[0074]
(1) In the present embodiment, the bottom surface 72 of the recess 71 is formed into a curved surface along the surface of a virtual cone having the axis O as the axis. Further, the tip surface 62a of the second magnetic flux passage ridge 62 is formed into a curved surface along a virtual spherical surface with the center point C as the center. Therefore, even if the yoke 36 is slightly rotated in the circumferential direction around the center point C due to the residual angular gap of the bearing 40, the width of the gap between the bottom surface 72 and the tip surface 62a hardly changes. Therefore, as compared with the conventional driving force transmission device 11, the driving force transmission device 111 according to the present embodiment can stabilize the attractive force of the armature 35 due to energization of the electromagnet 33. As a result, the driving force transmission device 111 can form the gap between the bottom surface 72 and the distal end surface 62a narrower than the driving force transmission device 11. Moreover, the front end surface 62a and the bottom surface 72 do not collide with each other, and abnormal noise, chatter, wear, chipping, and the like due to the collision can be prevented. In addition, since there is no wear or chipping due to the collision between the tip surface 62a and the bottom surface 72, the magnetic flux density passing between the tip surface 62a and the bottom surface 72 can maintain the initial state of assembly.
[0075]
(Fifth embodiment)
Next, a fifth embodiment of the present invention will be described with reference to FIG. In the present embodiment, the same parts as those in the first embodiment are denoted by the same reference numerals, detailed description thereof is omitted, and only different parts are described.
[0076]
In the driving force transmission device 121 of the present embodiment, the fourth magnetic flux passage ridge 64 is omitted, and a recess 73 is formed on the rear end side from the portion where the fourth magnetic flux passage ridge 64 is formed. Yes. The bottom surface (surface) 73a of the recess 73 is formed in a curved surface along a virtual spherical surface with the center point C as the center. Moreover, the 3rd magnetic flux passage protrusion 63 of this embodiment protrudes long compared with the 3rd magnetic flux passage protrusion 63 of a prior art. The tip surface 63a of the third magnetic flux passage ridge 63 is formed in a curved surface along a virtual spherical surface with the center point C as the center.
[0077]
In the present embodiment, the first magnetic flux passage ridge 61 and the third magnetic flux passage ridge 63 correspond to protrusions, and the front end surface 61a and the front end surface 63a correspond to second opposing surfaces. Moreover, the 2nd magnetic flux passage protrusion 62 is corresponded to a protrusion part, and the front end surface 62a and the bottom face 73a are equivalent to a 1st opposing surface.
[0078]
Next, the operation of the driving force transmission device 121 of the fifth embodiment will be described.
Even if the yoke 36 is slightly rotated in the circumferential direction around the center point C, the width of the gap formed by the two end faces 61a and 62a hardly changes, and the gap formed by the tip face 63a and the bottom face 73a Since the width of the gap hardly changes, the width of the gap can be designed to be as narrow as possible. Therefore, the force that the electromagnet 33 attracts the armature 35 and the magnetic flux density that passes through the magnetic path Z are more stable than the driving force transmission device 81 of the first embodiment.
[0079]
Therefore, according to the driving force transmission device 121 of the fifth embodiment, it is possible to obtain the same effects as the effects (1) to (7) of the first embodiment and the following effects.
[0080]
(1) In the present embodiment, the bottom surface 73a of the recess 73 and the tip surface 63a of the third magnetic flux passage ridge 63 are also formed on curved surfaces along a virtual spherical surface with the center point C as the center. Therefore, even if the yoke 36 is slightly rotated in the circumferential direction around the center point C due to the residual angular gap of the bearing 40, the width of the gap formed by the tip surface 63a and the bottom surface 73a hardly changes. Therefore, as compared with the driving force transmission device 81 of the first embodiment, the driving force transmission device 121 of the present embodiment can stabilize the attractive force of the armature 35 by energization of the electromagnet 33. As a result, the driving force transmission device 121 can form the width of the gap formed by the tip surface 63a and the bottom surface 73a to be narrower than that of the driving force transmission device 81. Further, the tip surface 63a and the bottom surface 73a do not collide with each other, and abnormal noise, chattering, wear, chipping, and the like due to the collision can be prevented. In addition, since there is no wear or chipping due to the collision between the tip surface 63a and the bottom surface 73a, the magnetic flux density passing between the tip surface 63a and the bottom surface 73a can maintain the initial state of assembly.
[0081]
(2) In the present embodiment, the bottom surface 73 a that forms a curved surface (a curved surface along a virtual spherical surface with the center point C as the center) is formed in the recess 73. That is, the bottom surface 73 a is formed at the corner of the step portion of the yoke 36. Therefore, it is easier to form the same curved surface as the bottom surface 73a than in the case where the curved surface is formed in a flat portion that is not a stepped portion.
(Another example)
In addition, you may change each said embodiment as follows.
[0082]
In the first embodiment, the second magnetic flux passage ridge 62 is formed so that the tip surface 62a can always face the entire surface of the tip surface 61a even when the yoke 36 rotates in the circumferential direction. . The first magnetic flux passage ridge 61 may be formed so that the tip surface 61a can always face the entire surface of the tip surface 62a even when the yoke 36 rotates in the circumferential direction. Such a change may be embodied in the second and fifth embodiments.
[0083]
In the first embodiment, the first magnetic flux passage ridge 61 and the second magnetic flux passage ridge 62 are adapted to the driving force transmission device 81 including the main clutch mechanism 30c and the pilot clutch mechanism 30d. For example, one corresponding to the first magnetic flux passage ridge 61 and the second magnetic flux passage ridge 62 may be applied to a driving force transmission device including one friction clutch. That is, there is no pilot clutch mechanism, the friction clutch mechanism of the main clutch mechanism is sandwiched between the electromagnetic coil and the armature, and the attraction force to the armature is adjusted according to the voltage current to the electromagnetic coil, so that the main clutch mechanism directly The present invention may be applied to a driving force transmission device configured to control the fastening force. Such a change may be embodied in the second to fifth embodiments.
[0084]
Next, technical ideas that can be grasped from the above embodiments and other examples will be described below.
(A) The driving force transmission device according to claim 1, wherein the first facing surface is disposed in a recess.
[0085]
  (B) The second facing surface is disposed in a recess.1The driving force transmission device according to 1.
[0086]
【The invention's effect】
  As detailed above,eachClaimIn termsAccording to the described invention, the attractive force of the armature by energization of the electromagnet can be stabilized.
[Brief description of the drawings]
FIG. 1 is an enlarged cross-sectional view of a main part of a driving force transmission device according to a first embodiment.
FIG. 2 is an enlarged cross-sectional view of a main part of a driving force transmission device according to a second embodiment.
FIG. 3 is an enlarged cross-sectional view of a main part of a driving force transmission device according to a third embodiment.
FIG. 4 is an enlarged cross-sectional view of a main part of a driving force transmission device according to a fourth embodiment.
FIG. 5 is an enlarged cross-sectional view of a main part of a driving force transmission device according to a fifth embodiment.
FIG. 6 is an explanatory diagram of a vehicle equipped with a driving force transmission device according to the prior art.
FIG. 7 is a partial cross-sectional view of a conventional driving force transmission device.
FIG. 8 is an enlarged cross-sectional view of a main part of a driving force transmission device in the prior art.
[Explanation of symbols]
81, 91, 101, 111, 121 ... Driving force transmission device, 30a ... Outer case as outer rotating member, 30b ... Inner shaft as inner rotating member, 33 ... Electromagnet, 34 ... Friction clutch, 35 ... Armature, 36 ... A yoke, 40 ... a bearing as a radial bearing, 61 ... a first magnetic flux passage ridge as a protrusion, 61a, 63a, 70 ... a tip surface as a second facing surface, 62 ... a second magnetic flux passage ridge as a protrusion. , 62a: a tip surface as a first facing surface, 63: a third magnetic flux passage ridge as a protruding portion, 71a, 72: a bottom surface as a second facing surface, 73a: a bottom surface as a first facing surface, Z: magnetism Road.

Claims (4)

An inner rotating member and an outer rotating member positioned so as to be capable of relative rotation, a friction clutch for transmitting torque between the inner rotating member and the outer rotating member, an armature disposed opposite to the friction clutch, and the friction clutch in comprising a counter arranged electromagnet to the armature, a yoke for supporting the electromagnet, and a bearing for rotatably supported through a gap the same yoke to the outer rotary member,
By energizing the electromagnet, a yoke, an outer rotating member, a friction clutch, an armature, a friction clutch, an outer rotating member, and a magnetic path that circulates the yoke are formed, and the electromagnet attracts the armature to frictionally engage the friction clutch And a driving force transmission device configured to be in a connected state capable of transmitting torque by the friction engagement force of the friction clutch.
The first opposing surface is a surface facing the outer rotating member in the magnetic path of the yoke is formed in a curved surface along the imaginary sphere centered on the center point of the bearing Rutotomoni,
A driving force characterized in that a second facing surface, which is a surface facing the yoke, in the magnetic path of the outer rotating member is formed as a curved surface along a virtual spherical surface centered on the center point of the bearing. Transmission device. The driving force transmission device according to claim 1, wherein the bearing includes an inner ring, an outer ring, and a bearing ball disposed between the inner ring and the outer ring. 3. The driving force transmission device according to claim 1, wherein the first facing surface is disposed in a protruding portion that protrudes toward the outer rotating member. 4. Said second facing surface, the driving force transmission apparatus according to any one of claims 1 to 3, characterized in that disposed in the protrusion protruding toward the yoke.

Images